DESCRIPTION (Adapted from the applicant's description): Vulvodynia is a syndrome of unexplained vulvar itching, burning, and/or pain that causes major physical and psychological distress. It is a diagnosis of exclusion when vulvar discomfort becomes chronic over many months and the presence of any other remediable cause, such as infection or dermatitis, is ruled out. The two major subtypes of vulvodynia -- generalized vulvar dysesthesia and vestibulodynia -- are often misclassified. Few descriptive or etiologic epidemiological studies have been performed. Thus, the prevalence and incidence in the general population is unknown and no preventable exposures have been identified. A recent NIH sponsored consensus conference stressed the need to determine the prevalence of vulvodynia and conduct population-based observational studies to identify modifiable risk factors. The applicant has conducted a population-based prevalence survey in more than 400 women that achieved a 70% response rate and found that 18% of women reported a lifetime history of chronic vulvar symptoms that lasted three months or longer. Approximately 8% of all women surveyed were currently experiencing these symptoms. In addition, the applicant conducted a pilot case-control study of 31 women diagnosed with either dysesthetic vulvodynia or vestibulodynia, or a combination of the two within the last five years and compared them to 31 similarly aged healthy women identified from the general population. Cases were, on average, three times more likely to report medical treatments or surgical procedures for conditions that may have influenced perineal pain, or a greater frequency of condom use and use of talcum powder in the genital area that may have lead to mucosal abrasion and inflammation. The applicant now proposes to survey 16,000 women 20-59 years of age from the general population to estimate the age-specific prevalence of vulvodynia. From this sample, the applicant will identify 400 cases of vulvodynia, verified through a two-step screening process, and a sample of 400 frequency matched age and county of residence controls. Structured interviews will assess a wide spectrum of exposures related to trauma. A subsample of 80 cases and 80 controls will receive a clinical examination to confirm the presence or absense of vulvodynia, and also will provide a vaginal lavage and vulvar swab specimen for the assessment of cytokines and the culturing of microbiological organisms. The applicant hypothesizes that various types of vulvar trauma may precede the spontaneous and evoked vulvar pain experienced by women with vulvodynia and that vulvodynia may be a variant of a specific type of Complex Regional Pain Syndrome that is consistent with sensory disturbances such as mechanical allodynia.